varieties & plant nutrition

March 22, 2011, The Art & Science of Fruit Culture, Day 2
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As I write this, I understand that the prompt for our journal entries is to write down some things we learned in a day and our reflections about the information learned. I decided to write a blog because I thought it would be fun to share what I am learning with my friends and family who are not here with me as I embark on this second round of college education. I would like to keep this blog going while I'm here at MUM, as I continue through other classes because this experience of being in school again is very important to me. I'll begin this blog by sharing some facts about what I learned today, and I see where it takes me.

The purpose of tree growth is to go toward the light. Growers use knowledge of Horticulture to distribute fruit in a more favorable formation on a tree. Without tree-training or pruning, most of the fruit would end up at the top area of the tree (closer to the sun), and that is not so favorable for us. It's easier if the fruit is distributed more equally throughout the tree. I could be wrong about this, but I think it also has something to do with overall longer term health and production of the tree to train it to distribute fruit more equally throughout the tree. Something really cool that I've learned is that the existence of leaves on a tree is not just ornamental (I never thought that was the case, but I guess I never thought too much about the role of leaves), and that leaves actually serve to grab sunlight and transform it into sugars that feed into the sweetness of the fruit. Horticulture is about using tree knowledge to balance leaf-to-flower ratio so that current year harvest will produce favorable results and that next year's harvest will also be favorable by balancing the number of spurs on each branch.

Today, we overviewed varieties of apples, cherries, European pears, Asian pears, peaches, hazelnuts, walnuts, chesnuts, (I forgot to mention that we also cover tree nuts in this class), figs, paw-paws (fruit native to America and it might be particular to Mid-west, I can't remember--also known as the custard apple or Indiana banana) and persimmons. The apple varieties we covered in class were vast. Some we learned were scab- and/or mildew- resistant. I was pretty familiar with most of the European and Asian pears, because we sold most all of them at my store. I don't know if it is true for Asian pears, but most European pears (with the exception of Bartlett) have to be treated by hanging out in cold storage (at around 32 degrees F) for a little bit until they can be suitable for eating. I didn't know that until today.

My indoor purple basil plant, SF 2010

I have not studied chemistry since sometime in high school. My last chemistry class might have been around 1997. So today, it felt a little challenging when we began talking about plant and soil nutrition. I had always been drawn more to physics--things that can be seen with the eye, or felt by the body. Chemistry was daunting, the Periodic Table seemed so confusing. All those little letters were present in different amounts all over the place, and they would connect to each other in different ways, and each seemingly minute change would produce profoundly different results. Is everything made out of chemistry? This keyboard? I don't know. How do we know the elements exist? How do we know their rules? I remember wondering in high school if the unit of each element was an atom. And for some reason, I remember going away with the sense that elements and atoms were separate things. I don't know to this day the difference, but I look forward to making friends with chemistry, and to hopefully learn a decent amount of it to successfully grow food some day.

I'll begin now by fumbling through this material. Something important to know about growing fruits and nuts is this combination N-P-K (Nitrogen, Phosphorus, & Potassium). But I think that is what the soil needs? Because I have written down here in my notes that fruit and nut trees need Nitrogen, Potassium and Boron, along with occasionally some other minor elements. Mature trees can use 1-1.5 pounds of actual Nitrogen per tree annually. Potassium can be applied in a band at the rate of 6-8 pounds of K2O per tree every five years. Boron can be applied as a spray of soluber or ground Boron application every few years. At the moment, it is unclear to me if NPK is important, why also is Boron important?

Part of being a grower is learning how to know if your plant is getting enough of what it needs. If a tree is nitrogen deficient, there is a yellowing of older leaves first because N is mobile in the plant. Sulfur deficiency causes yellowing on new leaves, I think because Sulfur is immobile in the plant. This is another thing to know about plant nutrition: the difference of elements being mobile or immobile in the plant and/or soil. We talked about other deficiencies, such as Iron, Phosphorus, and Potassium, but I missed writing those down. The final thing we talked about with nutrition is that Boron, Sulfur and Chlorine are mobile in the soil. Calcium, Magnesium are immobile in the soil. Iron, Manganese, Copper, Zinc and Molybdenum are extremely immobile. As for what this means exactly, and the ramifications of what it means, I don't really know yet! :)

I have a lot more to say about my interest in plant nutrition, and maybe it will come out later! I have had a few plants in my life who could have benefit from me having a little more knowledge in plant nutrition. Overall, I am really drawn to taking care of plants, but plants intimidate me! They are so mysterious and wise, and I don't understand how they talk. How they intimidate me reminds of how other people used to make me nervous. I used to worry so much about talking to strangers/new people because I didn't know them at all and didn't know where they were coming from or if they would like what I would have to say. This is how I feel writing this blog about Fruit Culture, very awkward to enter into a new set of knowledge with its own language in this world. But I am excited to be here, studying this because I want to learn the language of growing things, and I would like to learn the language of plants!